Panelboard



Nov. 11, 1941. w. H. FRANK E1- AL 2,261,987

PANELBOARD Filed Feb. 21, 1940 2 Sheets-Sheet 2 I INVENTOR BY K W 02?.33W

ffw wk ATTORNEY.

Patented Nov. 11, 1941 2,281,987 PANELBOABD WflllamH.FrankandRbertLmnk,

to Bulldog Electric Mich, assignora Company, Detroit, Mich. v llnlaDetroit, Products a eorporatlonpf Welt Application February a1, 1940,Serial No. 320,118 Claims. (01. ins-ans) 1lzagd to the appendeddrawings. In these draw- 8 This application relates to panelboards.

A panelboard, particularly when designed for flush mounting. generallyincludes a sheet metal box having an open front closed by an aperturedtrim plate, secured to the sides of the box, and in'whose aperture isdisposed the front of the panel mounted within the box, th panelgenerally having a mounting plate on which the units of the panel arethemselves mounted. For panelboards there have been provided numerousand various arrangements for mounting the panel in the box and forobtaining the necessary accurate leveling and alignment of thepanelboard parts with respect to one another and to the plaster of thewall in which the panelboard is to be disposed. L

This application discloses a novel arrangement for mounting a panel in abox and for accurately leveling and aligning the panelboard parts.

One common fault of the various arrangements provided for leveling andaccurately aligning the panelboard parts is the feature that thesearrangements require some degree of manipulation by th installingelectrician and these installers often neglect to manipulate theleveling arrangements and thus attain accurate leveling and aligning ofthe panelboard parts. This fault is not inherent to the arrangementherein dis closed since this arrangement is automatic in its operation,insuring accurate leveling and aligning of the parts without requiringany manipulation for this purpose by the installer.

Another featur of the arrangement herein disclosed for mounting panelsin panelboards is the convenience'of its use and the ease with which apanel may be mounted in or removed from a box Still another feature isthe simplicity of the panel mounting arrangement herein shown.

Still another feature is the characteristic that the mountingarrangement provides a two position mounting for the panel. In oneposition the panel is deepwithin th box. In another position the panelis projected considerably in front of the box, whereby access to theterminal connection screws on the vertical sides of the panel, that isto say on ends of the units of the panel, is provided.

Another feature is the characteristic that the panel is permitted tohave a limited amount of sidewise shifting in the box, to permit play,and,

to give greater access to the sides of the panel. For an understandingof the mounting ar- Fig. 1 is a front view with trim plate removed;Figs. 2 and 3 are transverse views showing two for the panel, and withthe form of Fig. 3 providing two different positions of the panel.

Fig. 4 is another transverse view but showing the trim plate in place.

Fig. 5 shows a unit of the panel.

Fig. 6shows a connector for the panel.

The drawings show a flush mounted panel board disposed in a recess of awall I 0 and including a box H having a vertical back l2, vertical andhorizontal sides I3--Il, and an open front normally closed by a trim.plate l5 secured to the box by screws l6 and having a large centralopening in which is disposed the front portion of a panel referenced asa whole I! and consisting of numerous units It mounted on a 4, 1938,except that they have rocker handles 20 instead of the rotary handlesshown in the patent. The vertical sides of the panel l1, that is to saythe ends of the units is are formed with branch conductor terminalbinding means 2|, and at the fronts of the units are the switchinghandles 20, these projecting beyond the trim plate so as to beaccessible for switching manipulation.

Theunits, as shown in Fig. 5, may have, in addition to the loadconductor binding means 2 I, and instead of similar binding means forthe line conductors; as in Figs. 3-4, flexible line conductors 22projecting from ends thereof and terminating in lugs 23 adapted to beconnected, by studs 24 to binding means 25 mounted on blocks 26 securedto the box back, between the panel and the box sides. The supply lines2'! for the panel may be connected to the binding means 25 forconnecting the panel to the supply.

The studs 24 may be replaced by bus bars, not shown, but similar in formto the neutral bar 28, and arranged to extend vertically and having manystuds to which may be connected individually.

For mounting the panel a novel panel mounting arrangement has beenprovided and the same will now be described.

. Spring leaves 30 are secured, as by rivets 3|, to the back of the box,and project forwardly. These leaves are positioned one above and one thelugs 23 rangements herein disclosed, reference should be below thehorizontal edges of the panel mountof the panel,

2 ing plate l9, engaging such edges between shoulders 32 of the mountinsplate which limit movement of the panel with respect to the leaves andthe box horizontally towards the vertical sides of the box. Limitedsidewise movement is desirable to permit the panel to align itselfaccurately to the aperture in the trim plate.

If desired, the distance between the shoulders 32 of the mounting platemay be made considerably greater than the width of the spring leaves topermit the panel to be slid a considerable distance sidewise and givegreater access to either side of the panel and facilitate wiring.

The leaves have horizontally extending facing grooves 33 formed by beadsand these grooves receive horizontal edges of the panel mounting plateI9, between the shoulders 31.

The use of the mounting arrangement herein shown is as follows:

When a panel is to be mounted in a box, the lower edge of mounting plateI! is seated within a groove 33 of the lower spring leaf 3|! which thentakes the weight of the panel, and then the upper part of the panel isswung rearwardly until the upper edge of mounting plate 19 snaps intogroove 33 of the upper spring leaf.

After a panel is inserted into the box in the manner just described andmounted therein on the spring leaves 30 the trim plate I! may be appliedto the front of the box with the edge of its central aperturetelescoping the panel, being in front of and abutting ledges 36 on theends of the units, that is, on the vertical sides of the panel. Theinstaller will push the trim plate rearwardly, manually and by threadingdown of screws l6, until the trim plate fits close against the wall Inand this will push the panel back as much as necessary for leveling, thefront of the panel however, at all times, tightly closing and fillingand engaging the edges of the trim plate hole for satisfactory leveling.

Most often the panel will be forced back sufilciently to cause itsmounting plate I! to leave grooves 33 of the spring will slide backalong these leaves, as in Fig. 4, as much as necessary to givesatisfactory leveling at the front. The spring leaves, even under suchconditions, will still support the panel in the box resiliently andsatisfactorily, with sidewise shifting of the panel being controlled bythe shoulders 32 of the mounting plate between which are the springleaves.

On removal of a trim plate, the panel will slide downwardly andforwardly a slight distance and the leaves will move toward each otheruntil the edges of the mounting plate are once more seated in thegrooves 33 of the leaves 30 and thus removal of a mounting plate willnot cause the panel to drop out of the box.

For removal of a panel it is necessary for the user to raise the freeend of the upper spring leaf to clear the groove of that leaf from theupper edge of plate l9, after which the upper part of the panel may beswung forwardly to clear the box and then the panel may be lifted offthe lower leaf 30 and out of the box.

It will be seen that accidental removal of a panel from a box isimpossible. The panel cannot fall out or be pulled out in any way exceptby raising the free end or forward end of the upper spring leaf and thisis not apt to happen except with the intent of the user. Any applicationof force tending to pull the panel forward, except when the forward endof the upper spring leaf is raised, will tend to enhance the grippingleaves 30 and the panel action of the spring leaves and the grooves onthe panel, and thus'defeat any tendency'of the panel to be pulled outexcept intentionally.

Whenthe trim plate is mounted the panel location is determined by thattrim plate for the trim plate can cause the panel to move sidewise aswell as forward and back on the spring leaves, sidewise play beingdetermined by the relative width of the spring leaves and the distancebetween the shoulders 32 and the mounting plate, and rearward positionbeing determined by the rearward thrust of the trim plate on the panel.

In the embodiment of Fig. 3 the leaves are longer than the correspondingleaves of the embodiment shown in Fig. 2 and are provided with a secondset N of grooves, forward of the set 33; these provide a mounted andsupported position of the panel considerable forward of the positionprovided when only one set of grooves 33 is formed on the spring leaves.The forward position determined by the grooves 34, gives greater accessto the terminal binding means 2| on the sides of the panel, projectedwell forward of the box, but still supported by the box and its springleaves.

Now having described shown, reference should be follow.

We claim:

1. A box having sides, a back and an open front, a device within thebox, and sufllciently smaller than the box to be remote from the boxsides, a trim plate secured directly to the box independent of thedevice and having an aperture providing access to the front of thedevice, the aperture being so small that its edges are remote from thebox sides, the device having portions engaging the rear surface of thetrim plate and portions projecting into the aperture of the trim plateso as to fill it, spring leaves permanently secured to the box andformed for detachably interlocking to the edges of the device forsupporting it and for biasing it towards and against the trim plate toclose the apertur thereof, the spring leaves supporting the device,independently of the trim plate, in the absence of the trim plate fromthe box.

2. A box having sides, a back and an open front, a device within thebox, and sufiiciently smaller than the box to be remote from the boxsides, a trim plate secured directly to the box independent of thedevice and having an aperture providing access to the front of thedevice, the aperture being so small that its edges are remote from thebox sides, the device having portions engaging the rear surface of thetrim plate and portions projecting into the aperture of the trim plateso as to fill it, spring leaves permanently secured to the box andformed for detachably interlocking to the edges of the device forsupporting it and for biasing it towards and against the trim plate toclose the aperture thereof, the spring leaves supporting the device,independently of the trim plate, in the absence of the trim plate fromthe box, the leaves being arranged above and below the device so thathorizontal edges thereof are gripped by the leaves.

3. A box having sides, a back and an open front, a device within thebox, and sufficiently smaller than the box to be remote from the boxsides, a trim plate secured directly to the box independent of thedevice and having an aperture providing access to the front of thedevice, the aperture being so small that its edges are remote from thebox sides, the device having the panel board here had to be claims thatportions engaging the rear surface of the trim plate and portionsprojecting into the aperture of the trim plate so as to fill it, springleaves permanently secured to the box and formed for detachablyinterlocking to the edges of the device for supporting it and forbiasing it towards and against the trim plate to close the aperturethereof, the spring leaves supporting the device, independently of thetrim plate, in the absence of the trim plate from the box, the leavesbeing arranged above and below the device so that horizontal edgesthereof are gripped by the leaves, the upper leaf projecting forwardlyand upwardly from the box back, and the lower leaf projecting forwardlyand downwardly from the box back.

4. A box having sides, a back and an open front, a device within thebox, and sufilciently smaller than the box to be remote from the boxsides, a trim plate secured directly to the box independent of thedevice and having an aperture providing access to the front of thedevice, the aperture being so small that its edges are remote from thebox sides, the device having portions engaging the rear surface of thetrim plate and portions projecting into the aperture of the trim plateso as to fill it, spring leaves permanently secured to the box andformed for detachably interlocking to the edges of the device forsupporting it and for biasing it towards and against the trim plate toclose the aperture thereof, the spring leaves supporting th device,independent- 1y of the trim plate, in the absence of the trim plate fromthe box, the device having portions engaging the aperture edges wherebysidewise shifting of the device is restrained by the trim plate.

5. A box having sides, a back and an'open front, a device within thebox, and sufficiently smaller than the box to be remote from the boxsides, a trim plate secured directly to the box independent of thedevice and having an aperture providing access to the front of thedevice, the aperture being so small that its edges are remote from thebox sides, the device having portions engaging the rear surface of thetrim plate and portions projecting into the aperture of the trim plateso as to fill it, spring leaves permanently secured to the box andformed for detachably interlocking to the edges of the device forsupporting it and for biasing it towards and against the trim plate toclose the apertur thereof, the spring leaves supporting the device,independently of the trim plate, in the absence of the trim plate fromthe box, the device having portions engaging the apertur edges wherebysidewise shifting of thejdevice is restrained by the trim plate, thedevice being movable, while supported by the leaves, in a directionparallel to the-box .back, to respond to lateral shifting of the trimplate.

WILLIAM H. FRANK. ROBERT L. FRANK.

